Impact of olive-orchard cropping systems on some soil physical and chemical properties in southern Spain

Systems of cultivating olive trees in Southern Spain were studied with respect to selected soil physical and chemical properties. The traditional system to leave the ground bare encourages erosion and soil degradation of large areas of the Mediterranean region, including Jaen, southern Spain, where olive growing dominates the agricultural system. The elimination of the organic debris under the tree canopy, to facilitate harvesting, is a widespread practice that impoverishes the soils even further in the area. The use of plant cover in winter, to avoid competition for water, and growing crops in the summer improve the fertility of the surface horizon significantly and protect the soil against erosion through better soil structure and water infiltration.